The Nuclear Safety And Security Commission has authorized the use of new bolts that can firmly secure concrete structures in 29 operational nuclear power plants in the country. This measure aims to reduce the risk of significant equipment in the reactor core swaying or detaching due to earthquakes or vibrations.
The Nuclear Safety And Security Commission noted on the 25th that it had deliberated and approved the operational change plan for the nuclear utilization facility submitted by Korea Hydro & Nuclear Power during its 219th meeting. The approval includes common matters for 26 operational nuclear power plants and equipment replacements for Wolsong Unit 2, Shin Hanul Units 1 and 2.
In nuclear power plants, crucial equipment such as pumps, piping, and control devices are secured to concrete structures. The device used for this is called an "anchor bolt." Simply put, it acts like a large screw that embeds heavy machinery into the floor to prevent it from shaking.
The newly permitted "undercut anchor bolt" is a reinforced fastening method compared to the existing ones. Its structure, which digs in and grabs the concrete at the end of the bolt like a latch, ensures that it does not easily come loose even in earthquakes or significant impacts. The Korea Institute of Nuclear Safety (KINS) has determined that the performance test results meet safety standards.
Wolsong Unit 2 will replace the 48-volt (V) batteries and chargers installed in the uninterruptible power supply that provides electricity even in emergency situations. It was explained that the existing equipment has been phased out and is outdated, making the replacement unavoidable.
Shin Hanul Units 1 and 2 will also replace core power facilities such as chargers, voltage stabilizers, and inverters with new devices. This change is necessary due to difficulties in securing existing components following the supplier's closure. The new devices have also been confirmed to be safe based on performance testing.
A representative from the Nuclear Safety And Security Commission said, "Even after the operational change approval is completed, we will closely validate and inspect safety during the installation and operational process on-site."